1915I Casimir Funk 307 



These preliminary results had an importance that exitended be- 

 yond their application to beriberi. The substances isolated from 

 yeast or rice-polishings, were regarded of vital importance, hence 

 the name given to them, vitamines, a conception that found its com- 

 plete justification in the ntimber of pubHcations, on this subject, dur- 

 ing the last three years. Vitamines have proved to be constant con- 

 stituents of the diet, eqtial in importance to proteins, carbohydrates, 

 fats and salts, and not replaceable by any of these. 



Plants are evidently able to synthesize vitamines. The animal 

 organism possesses considerable synthetic capacity, as has recently 

 been shown, but itssupply of vitamines is obtained from the vege- 

 table kingdom, a rule from which there are no known exceptions. 

 Every animal so far investigated in this respect, when kept on an 

 artificial but chemically definite diet, or on a purified one, exhausts 

 its störe of vitamine and gradually declines. 



Beriberi is not the only disease due to dietary deficiency of vitam- 

 ines. Many other diseases, such as scurvy, infantile scurvy, Pel- 

 lagra, rickets, sprue, several nutritional disturbances in infants,* a 

 metabolism disease in cattle called " lamziekte," etc., are due to 

 deficiency of vitamines, and have been grouped under the name of 

 "deficiency diseases" or avitaminoses. These diseases have one 

 character in common : they are due to partial or entire deficiency of 

 vitamines in the food. Such deficiency causes very profound 

 changes in the functions of the central nervous System. All other 

 Symptoms, such as gastric symptoms, changes in the bones, influence 

 on the heart and skin, etc., are only the results of the changes in the 

 central nervous system. It is easy tö realize, there fore, that these 

 diseases are more easily prevented than cured. The changed nerves 

 (fatty degeneration) cannot be restored to the normal condition 

 after a certain stage of the disease is passed. This is an important 

 point for attention in the study of " deficiency diseases." 



We come now to our task of reviewing the whole subject as it 

 developed during the years 1913 to 1915, inclusive (to date).* The 

 distribution of the chapters accords with the arrangement in my book 

 on vitamines, and brings the latter work up to date. 



* Received for publication, May 24, 191 5. The author will review, for publi- 

 cation in the October, 1916, issue of the Biochemical Bulletin, the further 

 developments in vitamine research to October, 1916. [Ed.] 



